Mission Hills (and Point Loma) will always command a premium. I’ve never been a believer in “we’re running out of land,” but one thing they’re not building anymore are 1920’s spanish-style homes or craftsman bungalows or mid-century moderns.
Not saying they won’t come down (or haven’t already), just that they’ll still be premium areas for some time to come. I would agree though that Liberty Station probably doesn’t help the cause.